1. Field of the Invention
The present invention relates to crystals (crystal form A) of 5-[2-amino-4-(2-furyl)pyrimidin-5-yl]-1-methylpyridin-2(1H)-one, a compound effective for prevention and treatment for various diseases such as constipation, and processes for preparing the same.
2. Related Background of the Invention
5-[2-Amino-4-(2-furyl)pyrimidin-5-yl]-1-methylpyridin-2(1H)-one is a compound having adenosine receptor antagonism and being effective for prevention and treatment for various diseases such as constipation (see patent document 1). Patent document 1, Example 16 discloses 5-[2-amino-4-(2-furyl)pyrimidin-5-yl]-1-methylpyridin-2(1H)-one was obtained as crystals.
Patent document 1: WO 03/035639